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An anonymous reader writes "There are over 700,000 ham radio licensees in the USA and about 2 ½ million worldwide. Today, this international community of wireless communications devotees are celebrating World Amateur Radio Day, recalling the advances Amateur Radio Service has made for modern man. Their theme for 2012 is Amateur Radio Satellites: Celebrating 50 Years in Space in remembrance of the launch of the first Amateur Radio satellites OSCAR 1 on December 12, 1961 and the launch of OSCAR 2 on June 2, 1962. Their ranks have included people like Steve Wozniak of Apple and Jack Kilby who invented the integrated circuit, Dr. Karl William Edmark who invented the heart defibrillator, Scott Durchslag, the Chief Operating Officer at Skype, and Dr. John Grunsfeld of NASA and the Hubble Space Telescope. This is the 87th anniversary of the foundation."

In some sense, I am a ham because of the Internet. I like participating in a global communication system that is operated by its own users. It is unfortunate that there are so many laws standing in the way of ARS being used in lieu of 3G/4G (the most prominent being the ban on encrypted transmissions).

probably more with culture of this country to buy something instead of making your own. Decades ago only big companies and govt agencies had two-way radios, and only the stinking rich had telephones in their cars. But the amateur radio operator had all these because they either built their own or put surplus equipment to have wireless systems two-way conversations and phone calls. Even people that do computers are more in users catagory instead of writing their own code. Yes, it is tough do build your own w

Thanks for your cogent comments and replies. I LOVE the idea of being able to fix your own electronics (vs buying another). After building an electronic kit you have the ability to detect and fix many obvious electronic problems.

And please any AARL old timers around this thread. Would you help train a novice? Would you support a novice? Myself and others need this.

There is no such ban. There is a rule that says "data emissions using unspecified digital codes must not be transmitted for the purpose of obscuring the meaning of any communication," but that's a matter of intent. For instance, if one encrypts a remote control signal, not to obscure it's meaning, but for the purpose of protecting it from interference, that's legal. If one takes advantage of a ham license to communicate with a high power 802.11 A

Amateur Radio has evolved greatly since the early days of having huge receivers and transmitters. Today we have so many different modes - CW, PSK31, APRS, SSB, etc on many different bands with just a transceiver. We can even do satellites and even low power (QRP) operations with a transmitter as small as a tuna can! The best part is meeting people all over the world who share this great hobby. I am excited to see where it goes from here and the technologies it will bring for the future from the individual who has a "homebrew" project to the commercial radio manufacturers and other companies who provide us the "candy" we love to play with!

FYI my Unikoo one (also RTL2832, arrived two days ago) can tune below 30MHz and just over 2GHz. The tuner chip actually goes down to 0Hz but the sensitivity seems to drop off outside the advertised range (i.e. strong signals only. I can tune into the normal AM radio band at ~1MHz but can't see any signals.)

But on that note, does anyone know where SDR newbies like myself can go to discuss these things? There are a bunch of extremely narrowband transmissions all over the place and I have no idea what they

Software defined radios digitally sample incoming signals. They then process those signals via software algorithms rather than electronic circuitry. Some radios can actually sample huge regions of the radio frequency spectrum (one amateur radio receiver I am aware of can watch a 60 MHz spectrum). They can actually decode many signals at the same time. So, for example, you could be decoding and watching hundreds of CW conversations (morse code) happening across the spectrum at the same time.

All the hardware has to do is digitize the radio spectrum being sampled. All of the remaining processing can be changed by replacing software. Previously, changing the processing of the signals meant replacing or adding electronic circuits.

The algorithms are quite sophisticated. Signals can be isolated for better reception or fairly easily excluded in the case of interference. This has resulted in a tremendous improvement in radio receivers especially in recent years. Neat stuff.

I absolutely agree. And don't forget JT-65, which is an absolutely amazing mode for pulling extremely weak signals out of noise. It's in many ways the ultimate geeky hobby and there are so many ways to be involved. I wish I had gotten started years ago.

I quit BBSes because they only had a range of ~100 miles (the local area code). I was involved in HAM for a while but quit for the same reason. Nowadays with the internet my voice or text can reach the whole world.

You don't even need an Extra license. A General will get you most of what you need for long-range HF use. And good thing, because for a software guy with only light electronics experience, that Extra test is hard! General, OTOH, is a couple of weeks of flipping through the book and taking the test.--KF7SPZ

I got my Extra by the skin of my teeth (knowing a fair amount of E-mag physics helped me fake my way through some of it), but yeah, I wouldn't sweat the extra work (no pun intended) if all you want is the privileges. The general isn't much harder than the technician, but the extra is a LOT harder than the general, especially for the mild increase in privileges. Seriously, add it up and it's only around 500 kHz more spectrum, spread across the 80, 40, 20, and 15 meter bands. Privileges are otherwise ident

Over here in Australia, the Advanced class has a lot more privileges than the Standard class - compare the frequencies and permitted modes for Advanced [comlaw.gov.au] versus Standard [comlaw.gov.au]. Also Advanced are allowed 400W pX for modes C3F, J3E or R3E and 120W pY otherwise, whereas the Standard class only permits 100W for modes J3E and R3E and 30W pY otherwise.

That seems to make more sense than the US system of licensing. The extra is way too difficult relative to the general exam for the modest increase in privilege. I don't advocate making the extra simpler, but rather making the general a little more difficult. But the cat's out of the bag, I guess.

I quit BBSes because they only had a range of ~100 miles (the local area code). I was involved in HAM for a while but quit for the same reason. Nowadays with the internet my voice or text can reach the whole world.

Well your voice or text can reach the whole world that's not blocked by their country's (or your own) firewall.

But, living in earthquake country, I became a ham so my voice can be heard even if local communications infrastructure has been destroyed. And through ARES [arrl.org], I can help others.

700K is a lot but real question is how active? Licenses these days are good for ten years (and with many hams of senior citizens, some may die of old age before license expires). I haven't run the numbers but I think many of these are Tech licenses, relatively easy to pass, i.e. one day Ham Cram. Much of this is promoted for emergency communications (however, many hams stress amateur radio is also a hobby that you can have FUN with experimentation). Plus the EMCOMM is in ways subsidized by DHS (local govts

It has been on my geek “bucket list” for many years to get my license. This story and a recent job change are just the motivation I needed to finally do it.

Now that the there's no Morse requirement, getting a tech license is trivial - any geek can do it with a couple hours glancing over a study guide. Most of the "technical" questions are common sense to anyone with a bit of electrical knowledge, so you just have to familiarize yourself with things that need to be memorized like license restrictions, power limits on various bands, etc.

Thanks. I believe I heard that from Leo Laporte on TWiT as well. I'm going to do it! Now the bigger issue: Will my wife kill me if I buy a nice ham rig? I do have a nice "man cave" in the basement with a spot for it:)

Thanks. I believe I heard that from Leo Laporte on TWiT as well. I'm going to do it! Now the bigger issue: Will my wife kill me if I buy a nice ham rig? I do have a nice "man cave" in the basement with a spot for it:)

Depends.

A nice radio (used) can be around $1000-2000+. A nice HF rig can be $5000+. And don't forget the antenna farm you need, so if your wife cares about the backyard, it can be an issue.

(If you have a PC, a fully kitted out Flex 5000 (HF+VHF/UHF, tuner, 2nd receiver) is only around $5000. B

But you can also put together a very workable station with only a few hundred or less. My first HF rig (IC-737) I got at a flea market for $300. Strung up a simple wire antenna on the back fence and five minutes later had my first QSO with Hawaii. My first VHF/UFH mobile rig was only $200 used and spent another $75 for the antenna and mag mount.

On getting a ham license. I got a technician license after the Loma Prieta earthquake. About 15 years later I had about two weeks of relative unemployment. In about a week using only Internet study resources I upgraded to General. In another 5 study days, using an online practice Amateur Extra exam, Wikipedia and a helpful website on electronics math, I passed the Extra Exam.

On ham radio equipment. The market for equipment like a solid state transceiver made in the last 20 years is extremely high priced, ba

Amateur radio seems to be overly restricted in the States. I have little interest trying to participate in a P2P communication system where encryption is explicitly forbidden. Also, the fact my country would prosecute me for communicating internationally with someone who lives under a repressive regime seems totally bogus.

If you're worried about privacy, with packet you can encrypt the data payload itself so long as the headers are not obfuscated and the transmission is properly identified.

Besides, privacy seems to be somewhat defeating of the purpose of Amateur radio. The spectrum set aside for hams is intended for educational use, and the ability to be heard is important so you can gauge the effectiveness of your rigs, vice versa for the other parties involved, learn how to make those improvem

If you're worried about privacy, with packet you can encrypt the data payload itself so long as the headers are not obfuscated and the transmission is properly identified.

Incorrect. Any use of ciphers or codes to obscure the meaning is prohibited, with the limited exception of control signals for space stations (47CFR97.113(a)(4)) [arrl.org]. That includes the bodies of packets sent via packet radio. That's the US law, perhaps you are referring to a different country?

Current software [winlink.org] in common use compresses the bodies of email messages sent via packet and pactor systems, but software can be used to decompress the messages and is thus not considered encryption.

Incorrect. Any use of ciphers or codes to obscure the meaning is prohibited,...

There was a forum discussion which someone complained, "so what if I want to talk like a CBer on ham radio? As long as I'm licensed and mention my callsign every 10 min, end of transmission, bla-bla, I can talk in whatever style I want!" However, someone gave example: "That's a big ten-four good buddy and I sure do appreciate that there smokey report on the five oh niner. Well, I'll catch you on the flipper flopper!" Bzzzzztttt. FCC Part 97 prohibits codes and ciphers used to obscure communications.

There was a forum discussion which someone complained, "so what if I want to talk like a CBer on ham radio? As long as I'm licensed and mention my callsign every 10 min, end of transmission, bla-bla, I can talk in whatever style I want!" However, someone gave example: "That's a big ten-four good buddy and I sure do appreciate that there smokey report on the five oh niner. Well, I'll catch you on the flipper flopper!"
Bzzzzztttt. FCC Part 97 prohibits codes and ciphers used to obscure communications.

I have little interest trying to participate in a P2P communication system where encryption is explicitly forbidden.

Some encryption is allowed, and the prohibition is against the use of codes or ciphers to obscure the meaning, not explicitely against all encryption. HSMM (ham WiFi) uses WEP (maybe WPA, I don't know) and gets away with it.

What's more important is that amateur radio isn't supposed to be used for things that would really require encryption anyway. No commercial use. You can't order a pizza, so you don't need to send anyone your credit card number, for example. The HSMM folks need to keep non-hams from usi

my country would prosecute me for communicating internationally with someone who lives under a repressive regime

AFAIK, there is no country that prosecutes licensed Amateur Radio Operators for communicating with Amateurs in any other country, regardless of their government. If a government permits the Amateur Radio Service as part of their telecommunications policy at all, then those Amateurs can communicate with any other Amateur anywhere, provided the other Amateur is duly licensed in his or her respectiv

I don't know about XBees, but WiFi shares one of its channels with Amateur Radio on a bases with the Amateur Radio operators allowed to interfere with Wifi, but not visa versa. Also I'd bet XBees have terrible receivers.

K7DGF here.. Been licensed since 1976, ex-WA6QNW, got the Extra in 1998. Kinda been inactive, due to the Internet. BUT.. I may just get back into it to play around with Gnuradio/SDR/IRLP/EchoLink.. Had no idea there ever WAS an "amateur radio day".. Too bad its not Field Day...